The pilot of an F-15 jet that crashed this week in remote Virginia mountains was killed, military officials said Thursday, bringing to a sad end an exhaustive two-day search involving more than 100 local, state and federal officials as well as volunteers.

Col. James Keefe announced the news at the Massachusetts Air National Guard in Westfield, Mass., home of the 104th Fighter Wing with which the pilot and jet were based.

Keefe said his "thoughts and prayers are with the family" of the pilot, whose identity wasn't disclosed.

The jet crashed in the mountains of western Virginia on Wednesday morning, shaking residents but causing no injuries on the ground.

Authorities said the pilot of the single-seat jet was headed to New Orleans for radar installation as part of routine maintenance and reported an inflight emergency before losing radio contact.

Officials haven't said whether the pilot ejected or what caused the crash, which left a deep crater and a large debris field in a heavily wooded but level area adjacent to a mountain in the George Washington National Forest.

They said an official safety investigation board is being convened and the investigation into the crash was ongoing.

Keefe said there were no munitions onboard the jet at the time of the crash. He said the plane was flying at about 30,000 to 40,000 feet when the pilot reported the emergency.

F-15s are maneuverable tactical fighters that can reach speeds up to 1,875 mph, according to the Air Force website. The F-15C Eagle entered the Air Force inventory in 1979 and costs nearly $30 million, the website says. The Air Force has nearly 250 F-15s.

Several F-15s have crashed over the past few years in various states. In at least one, the pilot ejected safely. Causes included failure of a support structure for the jet and pilot error.